Retrofitting of R404a Commercial Refrigeration Systems with R410a and R407f HFCs Refrigerants

2015 ◽  
pp. 260-294 ◽  
Author(s):  
Mauro Gamberi ◽  
Marco Bortolini ◽  
Alessandro Graziani ◽  
Riccardo Manzini
Keyword(s):  
Global Warming ◽  
Low Temperature ◽  
Global Warming Potential ◽  
Experimental Analysis ◽  
Cooling Capacity ◽  
Operating Conditions ◽  
Environmental Benefits ◽  
Medium Temperature ◽  
Air Temperatures ◽  
The Eu

This chapter presents an experimental analysis about the retrofitting of two commercial stationary refrigeration systems marketed by an Italian leading company of the sector. Such systems operate both at medium temperature (MT) and low temperature (LT) and they are originally designed to work with the high global warming potential (GWP) hydrofluorocarbon (HFC) R404a fluid (GWP = 3922). The purpose is to investigate the performances of HFCs R410a (GWP = 2088) and R407f (GWP = 1825) chosen as effective alternatives to HFC R404a, due to their compatibility, non-flammability and market availability. Furthermore, such fluids meet the EU restrictions in force in the next future for high GWP HFCs. The experimental analysis compares the performances, in terms of COP and cooling capacity, of R404a and the two identified alternatives under different operating conditions, i.e. chamber and condenser inlet air temperatures. In case of comparable performances, significant environmental benefits are introduced by the adoption of R407f and R410a in the MT and LT refrigeration systems.

Retrofitting of R404a Commercial Refrigeration Systems with R410a and R407f HFCs Refrigerants

2016 ◽  
pp. 160-192
Author(s):  
Mauro Gamberi ◽  
Marco Bortolini ◽  
Alessandro Graziani ◽  
Riccardo Manzini
Keyword(s):  
Global Warming ◽  
Low Temperature ◽  
Global Warming Potential ◽  
Experimental Analysis ◽  
Cooling Capacity ◽  
Operating Conditions ◽  
Environmental Benefits ◽  
Medium Temperature ◽  
Air Temperatures ◽  
The Eu

This chapter presents an experimental analysis about the retrofitting of two commercial stationary refrigeration systems marketed by an Italian leading company of the sector. Such systems operate both at medium temperature (MT) and low temperature (LT) and they are originally designed to work with the high global warming potential (GWP) hydrofluorocarbon (HFC) R404a fluid (GWP = 3922). The purpose is to investigate the performances of HFCs R410a (GWP = 2088) and R407f (GWP = 1825) chosen as effective alternatives to HFC R404a, due to their compatibility, non-flammability and market availability. Furthermore, such fluids meet the EU restrictions in force in the next future for high GWP HFCs. The experimental analysis compares the performances, in terms of COP and cooling capacity, of R404a and the two identified alternatives under different operating conditions, i.e. chamber and condenser inlet air temperatures. In case of comparable performances, significant environmental benefits are introduced by the adoption of R407f and R410a in the MT and LT refrigeration systems.

scholarly journals Refrigerating fluid with a low global warming potential for automotive air conditioning systems in summer

2021 ◽  
pp. 45-45
Author(s):  
Zhaofeng Meng ◽  
Yin Liu ◽  
Dingbiao Wang ◽  
Long Gao ◽  
Junhai Yan
Keyword(s):  
Global Warming ◽  
Global Warming Potential ◽  
Air Conditioning ◽  
Cooling Capacity ◽  
Automotive Air Conditioning ◽  
Discharge Temperature ◽  
Air Conditioning Systems ◽  
Low Global Warming Potential ◽  
Lower Discharge

Refrigerants with low global warming potential (GWP) are much needed in automotive air conditioning systems. This paper compares two refrigerants, R134a (GWP=1300) and R513A (GWP=573) experimentally. The results show that the latter has lower cooling capacity, lower COP and lower discharge temperature than the former, revealing that R513A is a promising replacement of its high GWP partner.

scholarly journals Modelling of Refrigerant Distribution in an Oil-Free Refrigeration System using R134a

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4792 ◽  
Author(s):  
Xinwen Chen ◽  
Zhaohua Li ◽  
Yi Zhao ◽  
Hanying Jiang ◽  
Kun Liang ◽  
...  
Keyword(s):  
Global Warming ◽  
Pressure Ratio ◽  
Cooling Capacity ◽  
Operating Conditions ◽  
Percentage Error ◽  
Two Phase ◽  
Phase Form ◽  
Compact Heat Exchangers ◽  
Micro Channels ◽  
Low Global Warming Potential

Increasing number of refrigeration units has led to an increase of CO2 emissions and the destruction of the ozone layer. Using low global warming potential (GWP) refrigerants, improving the efficiency of vapour compression refrigeration (VCR) units, and minimising refrigerant leakages can reduce the global warming effect. Investigating the refrigerant distribution under varied operating conditions can provide a deeper understanding of refrigerant charge optimization. This study proposed a model of refrigerant mass distribution in a prototype oil-free VCR system using a linear compressor with variable strokes and R134a. The absence of the oil lubricant allows the adoption of compact heat exchangers, such as micro-channels, so that the total refrigerant charge can be reduced significantly. The predicted total refrigerant charge has a Mean Absolute Percentage Error (MAPE) of 3.7%. The simulation results indicate that refrigerant distributed in the condenser is most sensitive to operating conditions and total refrigerant charges. The refrigerant accumulated in the condenser is 6.8% higher at a total refrigerant charge of 0.33 kg than that of 0.22 kg. For a total refrigerant charge of 0.33 kg, 72.1% of the total refrigerant can accumulate in the condenser. At a fixed pressure ratio, the refrigerant as a two-phase form in the condenser decreases slightly with the increase of compressor strokes, resulting in a larger mass flow rate, thus cooling capacity. The present model can be adapted for optimization of a refrigeration unit and its components.

scholarly journals Research on the effectiveness of alternative propulsion sources in high-tonnage cargo transport

2021 ◽  
Vol 60 (4) ◽  
pp. 259-273
Author(s):  
Mariusz Wasiak ◽  
Piotr Zdanowicz ◽  
Marcin Nivette
Keyword(s):  
Carbon Dioxide Emissions ◽  
Economic Assessment ◽  
Road Transport ◽  
Operating Conditions ◽  
Environmental Benefits ◽  
Total Carbon ◽  
Transport Sector ◽  
Exhaust Emission ◽  
Emission Standard ◽  
The Eu

The progressive degradation of the environment makes implementing pro-ecological solutions in various areas of our lives more meaningful. These measures also apply to transport, responsible for around 30% of total carbon dioxide emissions in the EU. Implementing ecological solutions in road transport encounters various barriers resulting mainly from the specificity of transport tasks. One of the most promising solutions in the high-tonnage road transport sector seems to be LNG-fueled engines, which allow for similar operating conditions to traditional combustion vehicles. The article aims to identify the environmental benefits of the use of high-tonnage LNG-fueled vehicles in freight transport and to conduct a comprehensive assessment of the economic efficiency of this solution. The article assesses the effectiveness of using an LNG-fueled vehicle and a diesel-fueled vehicle that meets the highest exhaust emission standard in high-tonnage transport, both in terms of economy and an impact of these solutions on the environment. The research was carried out on a given route, taking into account variants of vehicle manning and simulations of transport cycle time. In conclusion, a discussion of the obtained results was carried out, emphasizing the factors determining the profitability of using high-tonnage vehicles with LNG drive or its lack. Regardless of the indicated lack of clarity in the economic assessment of the effectiveness of LNG drives in high-tonnage vehicles, the identified environmental benefits from implementing these solutions seem to be quite unequivocal. Thus, it should be expected that in the event of loss of economic competitiveness of these solutions, appropriate fiscal instruments should be used - especially since LNG drives in the policies of individual countries are considered pro-ecological solutions.

scholarly journals Thermodynamic Analysis of Low GWP Refrigerant Mixtures in a Refrigerator as Replacement to R-134A

2019 ◽  
Vol 69 (4) ◽  
pp. 147-158
Author(s):  
Sk Mohammad Hasheer ◽  
Kolla Srinivas
Keyword(s):  
Global Warming ◽  
Global Warming Potential ◽  
Ozone Depletion ◽  
Global Climate ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Environmentally Sustainable ◽  
Discharge Temperature ◽  
R 134A ◽  
Volumetric Cooling

AbstractChlorofluorocarbons and hydro chlorofluorocarbons (HCFCs) are replaced by hydroflourocarbons (HFCs) which is not harmful to the ozone layer. However, few of HFCs have a relatively high global warming potential (GWP) and are subject to further examination due to growing concerns about global climate change. The goal now is to find the next generation of environmentally sustainable work fluids with an insignificant direct environmental impact in terms of ozone depletion and global warming potential. This document introduces the mixture of low-GWP refrigerants like R440A, R430A, R1234ze (E)/152a (50:50 by mass), R290/600a (40/60), R290/600(60/40), R290/600(50/50), ARM 42,ARM 42a and AC5 are used to replace R-134a in a domestic refrigeration system without doing any modifications to the system. The performance of the refrigerator was observed in terms of volumetric cooling capacity, blower discharge temperature, and coefficient of performance, refrigeration effect and energy consumption of a blower.

scholarly journals Experimental Analysis and Optimization of an R744 Transcritical Cycle Working with a Mechanical Subcooling System

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3204 ◽  
Author(s):  
Daniel Sánchez ◽  
Jesús Catalán-Gil ◽  
Ramón Cabello ◽  
Daniel Calleja-Anta ◽  
Rodrigo Llopis ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Heat Exchanger ◽  
Critical Temperature ◽  
Computational Model ◽  
Experimental Analysis ◽  
Experimental Tests ◽  
Cooling Capacity ◽  
Operating Conditions ◽  
Coefficient Of Performance ◽  
Liquid Heat

In the last century, the refrigerant R744 (carbon dioxide) has become an environmentally friendly solution in commercial refrigeration despite its particular issues related to the low critical temperature. The use of transcritical cycles in warm and hot countries reveals the necessity of adopting different configurations and technologies to improve this specific cycle. Among these, subcooling methods are well-known techniques to enhance the cooling capacity and the Coefficient of Performance (COP) of the cycle. In this work, an R600a dedicated mechanical subcooling system has been experimentally tested in an R744 transcritical system at different operating conditions. The results have been compared with those obtained using a suction-to-liquid heat exchanger (IHX) to determine the degree of improvement of the mechanical subcooling system. Using the experimental tests, a computational model has been developed and validated to predict the optimal subcooling degree and the cubic capacity of the mechanical subcooling compressor. Finally, the model has been used to analyze the effect of using different refrigerants in the mechanical subcooling unit finding that the hydrocarbon R290 and the HFC R152a are the most suitable fluids.

Experimental Evaluation on Low Global Warming Potential HFO-1336mzz-Z as an Alternative to HCFC-123 and HFC-245fa

2019 ◽  
Vol 11 (3) ◽  
Author(s):  
Shikuan Wang ◽  
Zhikai Guo ◽  
Xiaohong Han ◽  
Xiangguo Xu ◽  
Qin Wang ◽  
...  
Keyword(s):  
Global Warming ◽  
Global Warming Potential ◽  
Power Input ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Cycle Performance ◽  
Promising Alternative ◽  
Discharge Temperature ◽  
Low Global Warming Potential ◽  
Hcfc 123

HFO-1336mzz-Z with low global warming potential (GWP) was considered as a promising alternative of HCFC-123, HFC-245fa in air conditioning (AC) and heat pump (HP), respectively. In order to understand the operation performances of HFO-1336mzz-Z and HCFC-123, HFC-245fa in different working conditions, an experimental setup for testing the refrigeration cycle performance was built. The cycle performances of HFO-1336mzz-Z and HCFC-123 in AC conditions, HFO-1336mzz-Z and HFC-245fa in HP conditions were investigated by experiment. It was found in AC conditions, the discharge temperatures for the systems with HFO-1336mzz-Z and HCFC-123 were lower than 115 °C, the cooling capacity of the system with HFO-1336mzz-Z was 27% less than that with HCFC-123 at least, and the coefficient of performance (COP) of the system with HFO-1336mzz-Z was 0.1 lower than that with HCFC-123; in HP conditions, the discharge temperature with HFO-1336mzz-Z was lower than that with HFC-245fa, the former was never over 115 °C while the latter was up to 126 °C, the power input to the compressor with HFO-1336mzz-Z was 20% less than that with HFC-245fa in the same HP conditions, the heating capacity of the system with HFO-1336mzz-Z was 30–40% less than that with HFC-245fa.

scholarly journals Investigation and Analysis of R463A as an Alternative Refrigerant to R404A with Lower Global Warming Potential

Energies ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1514
Author(s):  
Piyanut Saengsikhiao ◽  
Juntakan Taweekun ◽  
Kittinan Maliwan ◽  
Somchai Sae-ung ◽  
Thanansak Theppaya
Keyword(s):  
Carbon Dioxide ◽  
Global Warming ◽  
Transport Properties ◽  
Global Warming Potential ◽  
Cooling Capacity ◽  
Coefficient Of Performance ◽  
Fourth Generation ◽  
Operating Pressure ◽  
Thermodynamic And Transport Properties ◽  
Carbon Dioxide Co2

This research presents the development of R463A refrigerant, a nonflammable refrigerant that was retrofitted to replace R404A. R463A is primarily composed of hydrofluorocarbons/hydrocarbons/carbon dioxide (HFCs/HCs/CO2), and has global-warming potential (GWP) of 1494. It is a nonazeotropic mixture of R32 (36%), R125 (30%), R134a (14%), R1234yf (14%), and R744 (6%). R463A is composed of polyol ester oil (POE), and it is classified as a Class A1 incombustible and nontoxic refrigerant. R463A has a higher cooling capacity (Qe) than that of R404A, as it is composed of hydrofluorocarbons (HFCs) R32 and carbon dioxide (CO2) R744, and has lower GWP than that of R404A due to the use of hydrofluoroolefins (HFOs) from R1234yf. The results of this research showed that R463A can be retrofitted to replace R404A due to its composition of POE, Class A1 incombustibility, and lower toxicity. The properties of R463A and R404A, as analyzed using national institute of standards and technology (NIST) reference fluid thermodynamic and transport properties database (REFPROP) software and NIST vapor compression cycle model accounting for refrigerant thermodynamic and transport properties (CYCLE_D-HX) software, are in accordance with the CAN/ANSI/AHRI540 standards of the Air-Conditioning, Heating, and Refrigeration Institute (AHRI). The normal boiling point of R463A was found to be higher than that of R404A by 23%, with a higher cooling capacity and a 63% lower GWP value than that of R404A. The critical pressure and temperature of R463A were found to be higher than those of R404A; it can be used in a high-ambient-temperature environment, has higher refrigerant and heat-rejection effects, and has lower GWP than that of R404A by 52% due to the HFOs from the R1234yf component. The cooling coefficient of performance (COPc) of R463A was found to be higher than that of R404A by 10% under low-temperature applications. R463A is another refrigerant option that is composed of 7% carbon dioxide (CO2), and is consistent with the evolution of fourth-generation refrigerants that contain a mixture of HFCs, HFOs, HCs, and natural refrigerants, which are required to produce a low-GWP, zero-ozone-depletion-potential (ODP), high-capacity, low-operating-pressure, and nontoxic refrigerant.

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